Building Regulations Approval: Full Plans vs Building Notice

Introduction

Building Regulations approval is required for most significant construction works in England — extensions, loft conversions, internal structural alterations, replacement windows (in some cases), and changes to services. There are two principal routes for obtaining Building Regulations approval for domestic works: the Full Plans application and the Building Notice. Understanding the difference between these routes — and when each is appropriate — helps homeowners and their architects manage the Building Regulations process effectively. A third route, using a private Approved Inspector rather than the local authority Building Control, is also available.

The Full Plans Route

What It Is

A Full Plans application involves submitting detailed drawings and specifications to the local authority Building Control (LABC) before construction begins. The LABC reviews the submission, checks it against the Building Regulations, and issues a formal Approval Notice (or requests amendments). Once Approval is obtained, construction can proceed in accordance with the approved drawings.

When to Use Full Plans

Full Plans is the preferred route for:

• Extensions, loft conversions, and new buildings — any project where the design should be confirmed before construction begins
• Complex structural projects where Building Control review of the structural design before construction provides useful assurance
• Projects where a completion certificate is needed promptly at the end of works for sale or mortgage purposes
• Any project where the LPA has required Building Regulations compliance as a condition of planning permission — the formal record of Full Plans approval is needed to demonstrate compliance

Advantages of Full Plans

• The LABC confirms compliance before construction — avoiding situations where compliant work has to be changed or demolished during construction
• Formal Approval Notice provides documented evidence of compliance for sale/mortgage purposes
• Identifies compliance issues early — amendments to the design can be agreed before the contractor mobilises, avoiding costly variations during construction
• A completion certificate is issued when the inspector is satisfied the completed works comply with the approved plans

Process and Timescales

A Full Plans application is submitted with the architectural drawings, structural calculations (where applicable), and specification. The LABC must determine the application within 5 weeks (or an agreed extension of up to 2 months). Where the application is complete and straightforward, approval in 4–6 weeks is typical. If the LABC requests amendments (conditional approval), these are agreed and the plans are re-approved.

The Building Notice Route

What It Is

A Building Notice is a simple notification to the LABC that works are about to begin. No drawings are submitted for approval in advance — instead, the Building Inspector visits the site at key stages and assesses the work in progress against the Building Regulations. No formal Approval Notice is issued; instead, compliance is assessed stage by stage as construction proceeds.

When Building Notice May Be Used

Building Notice is available for most domestic works (not for new dwellings or buildings subject to the Fire Safety Order). It is typically used for:

• Minor works where the structural and compliance issues are straightforward and can be easily assessed by an inspector on site
• Works where the contractor wants to begin immediately without waiting for full plans approval
• Small extensions or alterations where the design is not finalised in detail before construction begins

Disadvantages of Building Notice

• No formal approval is given before construction begins — if non-compliant work has been carried out, it must be opened up, modified or demolished at the contractor's or homeowner's expense
• A completion certificate is not issued under the Building Notice route — this can create difficulties when selling the property or applying for a mortgage, as purchasers' solicitors typically require evidence of Building Regulations compliance
• Building Regulations indemnity insurance may be needed to cover the absence of a completion certificate, at additional cost
• Not appropriate for complex structural projects where a detailed review of the structural design in advance is valuable

Approved Inspector Route

An alternative to using the LABC is to appoint a private Approved Inspector (AI) — a private company licensed to provide Building Regulations approval services. The AI acts in place of the LABC, reviewing plans, inspecting works, and issuing compliance certificates. The process and outcomes are the same as the Full Plans LABC route but with a private provider. Approved Inspectors are typically faster and more responsive than some LABCs. NHBC, RSA Group, and other specialist organisations provide Approved Inspector services. A Initial Notice must be served on the LABC to transfer jurisdiction from the LABC to the AI before works begin.

Which Route to Use

Conclusion

For most significant domestic works in north London — extensions, loft conversions, basement work — a Full Plans Building Regulations application (via LABC or Approved Inspector) is the correct and recommended approach. Building Notice should only be used for truly minor and uncomplicated works. The Full Plans route provides formal documentation of compliance, a Completion Certificate, and a clear record that is available for future sale or mortgage purposes. An architect preparing the Building Regulations submission will select the appropriate route for the project and manage the compliance process from submission through to completion certificate.